Fraternization
by HighQueen
Summary: "I love Eren," Mikasa insisted, gasping as Rivaille's hot tongue slid across her skin. "You may love Eren," he agreed, his voice like rough silk. "But you want me." Eren catches Mikasa and Rivaille in a compromising position, and is not happy. LeviMika RivaMika. ErenMika. LeviEren RivaEren Riren. Eventual LeviMikaEren RivaMikaEren. Rated M for threesome, smut.
1. Caught

_Disclaimer: I don't own Shingeki no Kyojin_

_Author's Notes: So, I got a lot of requests to write LeviMika. But ErenMika is my OTP. And I also kinda started liking LeviEren or Riren as they call it... so yeah... judge me all you want, I now ship all of them, though ErenMika is still my preferred pairing. So I decided to just write all three of them. In one fic. Yup. OT3. And bits of them individually too. _

_This will be about five chapters, mainly smut though some amounts of angst/fluff/character development. The chapters will be much shorter than my usual ones too. It's just a side project to keep me occupied as Losing Control goes through its beta stages, and to keep my mind off that story because its consuming me. _

_Don't ask me when this happens and how it makes sense with canon, because it doesn't._

_Also, unlike my other fics, I have called him Rivaille here rather than Levi. If people would rather I change that, let me know. _

**_Warning: Rated M for sMut. Contains: LeviMika ErenMika and LeviEren. And also LeviMikaEren RivaErenMika RivaMikaEren LeviErenMika or whatever you want to call it._**

**_But yes, eventually there will be a Levi x Mikasa x Eren threesome. This chapter is just LeviMika though, with mentions of onesided MikaEren._**

* * *

**Fraternization**

**Chapter 1: Caught **

* * *

Mikasa wasn't sure when it started, and how it got that way.

She was in love with Eren, after all. She breathed, fought, lived for the boy.

And yet, here she was, pressed back against a tree, Lance Corporal Rivaille's breath hot on her ears.

His hair tickled against her forehead, two fingers hooking under her belt. He yanked her forwards so that her clothed chest brushed against his.

"Give it up," Rivaille murmured, his hands finding her wrists.

She struggled against him, but he pushed back. He was strong, frightfully so. Nobody had ever been able to restrain her before. Whenever she got into scuffles with Eren, she always shoved him off. And yet, Rivaille held her there so effortlessly.

Mikasa hated him for it.

She hated that he was stronger than her.

And she hated the fact that all of it - his strength, his contemptuous gaze as he pinned her under him, his husky, condescending voice, the way he was able to overpower her and ridicule her and find faults with her in a way that no other soldier could - turned her on ridiculously.

"Fucking chibi," Mikasa spat at him. "Get off me."

Her eyes met his, flashing angrily. It was her glare of death. Rivaille's eyes were half-lidded, bored. It was as if she had no effect on him.

Rivaille's finger skated across the skin of her wrist, leaving a burning trail. He traced up her arm, her tense muscles, to her shoulder.

It was just one finger, he was barely touching her - and yet Mikasa just wanted, so badly, _wanted _him to -

"Eren won't mind," Rivaille drawled. "If that's what's worrying you."

"I - I Iove Eren!" Mikasa snarled at him.

"But you want me."

He sounded so confident, self-assured, that Mikasa wanted to punch him in the face.

But she couldn't.

Instead, she let him slide a knee between her legs, his hands gripping her waist. Mikasa felt herself grow wet as his thumbs circled her hipbones, slowly, languidly.

"I would never want you," she bit out, as he rubbed at her through her white pants.

"But you're already wet," Rivaille stated. "I've barely touched you."

Mikasa had nothing to say to that, no sharp retort.

It was true.

Mikasa loved Eren with all her heart, and sometimes, when he gazed upon her tenderly with his brilliant green eyes, or let her hold his hand - she felt her stomach flutter.

But it was so - _difficult, _loving Eren. So emotionally draining. He was so focused on his own ambitions, and he always whined about how she suffocated him with her attention.

And even though she did love him, she was always so busy protecting him, taking care of him.

There was a certain thrill to being with a man that didn't need her protection, a man that was stronger than her. A man more experienced than her, who could get under her skin, and probably kill her if she wanted.

Mikasa had always been overly strong, outclassing everyone else. And yet, Lance Corporal Rivaille outclassed her.

And more than anything, she was inexperienced. She had never experienced a man's touch. All she experienced was the emotional emptiness that came from loving Eren, and receiving nothing in return. She knew Eren would come to her eventually. But till then, as much as she tried to hide it, it was frustrating, unfulfilling.

And Rivaille knew this.

Mikasa gasped, as his hot tongue traced against of her ear. He nipped down against her skin, his hands sliding across to the inside of her thigh.

"Heichou -"

It came out as a gasp, even though she didn't mean it to.

"Stop denying it, Mikasa."

His voice was low, husky, and it sent chills down her spine. His lips moved down to her neck, as his hands parted her legs.

"You may be in love with Eren, but you're wet for me. You'd probably rather kiss him than kiss me, but it's my dick you want shoved into you, not his."

Mikasa's cheeks flushed red, though his crass words turned her on more than anything.

Rivaille lifted her up, his fingers skimming across her bottom, and ground against her. He was hard as well, and it gave her a deep satisfaction.

Mikasa wrapped her legs around him, digging her heels into his back to force him closer to her.

"This doesn't mean I despise you any less."

Rivaille smirked against her neck, amused by how acerbic her voice sounded.

"Say that to me again when I'm fucking you tonight."

Rivaille thrust against her, and she could feel him through the cloth of her pants, and she was wet, and it was a wonderful friction.

Mikasa let out a moan, and Rivaille nipped at her neck, before bringing his lips close to hers, hovering just centimeters away.

He undid the buttons of her white shirt with numb fingers - the fact that those very fingers were fingers of a killer, fingers that handled swords that had killed hundreds, no, _thousands _of Titans only served to turn her on more - and his hands ghosted across her stomach, her abs, up to her chest.

He undid her bra with one flick of his finger to give himself better access.

"_Heichou-" _she gasped, as his hands fondled her, but he shut her up by crashing his lips to hers.

It was Mikasa's first kiss, and it wasn't Eren. She had always wanted it to be Eren.

But Rivaille's lips were rough and demanding - just like him - and his teeth scraped against her bottom lip.

And he was touching her in such delightful ways that Mikasa found that she didn't mind.

"You're mine tonight," he whispered into his mouth. "I'm going to fuck you so hard that you won't be able to use your 3DMG for days without the pain, without remembering."

Mikasa felt her entire body blush at his words, his low, rough voice.

"Heichou-"

"Call me Rivaille."

He bit her lip, drawing blood, and Mikasa tugged at his silky black hair, her nails digging into his scalp.

"Rivaille."

She liked the way it rolled off her tongue.

Rivaille's hands went to her pants, flicking the button open.

"What are you -"

"It's just a taste of what you'll get tonight," he told her, sliding a hand into her.

Mikasa cried out loud then, as he rubbed her with his fingers.

"You're wetter than I thought. You're not going to last long this way."

He sounded almost condescending, and amidst the pleasure, Mikasa felt a surge of irritation.

_I'll show him._

* * *

It eventually became a habit.

The Lance Corporal treated her neutrally in public, maintaing a cold, calm disposition. But sometimes, he would grab her scarf in an empty corridor, and pull her in for a kiss.

Sometimes he would summon her to his office, and that's when things would get more serious.

He was always the same - teasing, condescending, patronizing - and with experience, she had gradually learned how to maintain control of her expression, of her voice.

She didn't give in to him so easily anymore. There was something thrilling about it, every time they had sex.

Of course, the sex was fantastic. They were both ridiculously athletic, with a lot of stamina, and using the 3DMG really toned the muscles.

But it was always what led up to the sex which excited her more. It was like a game - seeing who would give in first, seeing who was more affected by the other.

They always battled for dominance regarding who topped. Mikasa found that she would top one time out of four, but a part of her wondered whether it was because she really was able to overpower him, or because he let her.

"I like it when you ride me," he had told her once, his hands skimming over her bottom.

She had rode him hard that night, so hard that even he was panting and cursing at the end of it.

"Fuck, Mikasa. Fuck. You're fucking good. Do that again."

There was no emotion involved, or at least Mikasa didn't think so. It was good exercise though, and sometimes the positions Rivaille put her in were better practice in endurance and flexibility than 3DMG.

* * *

It happened two months after they had started their sick routine.

Mikasa was in Rivaille's office, clad in nothing but her pants, boots, and her 3DMG belts. He had left them on, even the ones that crossed across her chest.

It was some kind of fetish of his, she had guessed.

His state of undress mirrored hers, and Mikasa was running her hands over his gloriously toned chest, trying not to admire it too obviously as she sat on his lap, straddling him.

Rivaille, of course, caught it.

"Stop gaping so much," he told her, squeezing her breasts.

He leaned forwards to slide his tongue into her mouth, and she bit him.

"Bitch," Rivaille cursed.

Mikasa smirked, pulling on his neck to bring him back into the kiss. He kissed her forcefully, before pulling her way and dipping his head down to her chest.

"Oh - _oh_ -" Mikasa shut her eyes in ecstasy, pulling at his hair as his tongue swirled around her and he sucked.

It was at that moment, that the door creaked. Mikasa's eyes flew open, only to meet the wide, shocked, emerald gaze of one Eren Jaeger.

* * *

_Author's Note: Whoopsies. They should have locked that door. What will happen next? Please leave me a review and let me know what you think. I know, I know, I'm quite depraved. _

_Also, please note that this isn't going to be like my usual fics, and Eren and Mikasa will both act differently given the nature of this story. If anyone is interested in just ErenMika, check out my other stuff, I have smut, fluff and adventure too. If you want to read another LeviMikaEren (shameless self promotion) check out my fic **The King, the Queen and the Ace. **_

_Till then, please review and let me know if you like it! Is it worth continuing? I have another chapter half written and the third one planned too, so they should be up soon if all goes well. _

_Also, does anyone know of any good fics that ship this as an OT3? I'm surprised I haven't seen any around and I thought they would be really popular. They seem the obvious badass choice for an OT3. Also if anyone has good RiRen fic recs, let me know as well! Not the ones that are just fluff, or having him beating the crap out of Eren and getting off on it. But realistic ones with good character development, preferably not AUs. Thank you! _


	2. Confession

_Disclaimer: I don't own Shingeki no Kyojin_

_Author's Notes: Thank you SO much to all of those who reviewed yesterday! I really appreciated it, and honestly, it kind of made me want to update super fast for all of you, so here you go! Here's the second chapter._

_I appreciate those of you who read this just because you like my writing. But honestly, I'll warn you - this is going to include RivaMika ErenMika, a small amount of RivaEren smut, and RivaMikaEren threesome smut. So if you're really disgusted by any of those, I suggest you don't read. _

_This chapter is mainly ErenMika angsty stuff, with a tiny bit of fluff in the middle. It'll get better after the next chapter though, I promise you. That's when you'll start seeing some LeviEren/Riren and more MikaEren. _

_For those of you who are concerned I'm going to box Mikasa out of the OT3, fear not. I won't do that. I also don't intend to let this interfere with my other ErenMika chaptered fics, so don't worry._

_Till then, I hope you enjoy this chapter! I know this story is very different from what I've been usually writing. Mikasa's also rather emotional in this chapter. I think it works because that's how she is when it comes to Eren and now she's at a point where she has nothing to lose given what he's caught her in. It's hard writing them outside of the smut given the nature of this story!_

_Warning: Rated M for sMut. All warnings from previous chapter apply too._

* * *

**__Fraternization**

**Chapter 2: Confession**

* * *

"E-Eren!" Mikasa cried, her eyes locked with his dark green ones.

Eren's eyes were full of turbulent emotions - shock, betrayal, anger - and,Mikasa's heart nearly skipping a beat at the realization - a glimmer of _hurt. _

Rivaille bit down, his hands squeezing her possessively.

"It's Rivaille," he growled at her. "I trust you remember my name given the way you were screaming it out last nigh-mmf!"

Mikasa covered Rivaille's mouth with her hand, trying to ignore his tongue as it slipped through her fingers.

She turned his chin with her other hand, and Rivaille tilted his head back, bangs falling across his forehead.

He caught sight of Eren, who was still standing their and gaping at them.

"Eren. It's rude to stare."

Mikasa wondered how the hell he managed to keep his voice so calm, so condescending, despite the fact that Eren had walked in on them pretty much - she was so mortified that she couldn't even complete the thought.

"Also, remember to knock next time," Rivaille drawled. "As you can see, you've interrupted something important."

"The hell you are!" Eren exploded. "What the hell do you think you're doing to Mikasa?! Let her go!"

His eyes were blazing with fury, his form stiff with anger. And Mikasa's heart cracked. She wanted to go up to him and hug him and soothe him - but she was still entwined around Rivaille rather shamelessly.

He was probably just being protective in a brotherly way. But yet, it bothered him, Mikasa could see that.

_Oh, Eren... _

_"_Oh, I think Mikasa is quite happy to be here." Rivaille's voice was like silk, and he dragged his tongue along her neck, in full view of Eren, who looked like he was going to transform there and then, and start a rampage.

"Heichou," Mikasa hissed, her cheeks reddening as she slapped him away from her, hastily covering her bare breasts with her scarf, which lay in a heap or Rivaille's table.

_How much did Eren even see?!_

"You're lying!" Eren snarled at him, before his eyes locked with Mikasa's again. "Mikasa!"

Eren's voice was rough, but held a note of pleading.

"He forced you, didn't he, Mikasa? You had no choice, isn't that right? It's okay now, I'm here. You don't have to do that with him, I'll take care of you."

His voice was concerned, almost gentle. It was a tone she had always longed to hear from him, but never had. Eren hadn't spoken to her that way in five years.

Mikasa wanted to rip her hair out.

_Why now?!_

Eren held his hand out.

"Mikasa. Come on. It's okay. I won't tell anyone and we'll pretend it never happened."

Rivaille's grip tightened around her, his fingers trailing up her back.

"Yes, Mikasa. Go with him. And at night when you think of me, you can jerk yourself off. Or ask Eren to help you out, just make sure you don't cry out my name. That'll piss him off, the stupid brat."

"Shut up!" Eren shouted.

"Eren-" Mikasa's voice trembled.

"Shut the fuck up, and leave her alone! And stop saying shit like that!" Eren was furious.

"I say a lot of shit," Rivaille agreed, "but I'm telling the truth about this. Ask Mikasa yourself, why don't you?"

Rivaille turned to Mikasa, his expression sly, almost cunning as he met her gaze.

"Mikasa?"

There was a trace of doubt in Eren's voice, and Mikasa wanted to die. She fixed Rivaille with her most hateful glare.

"Your death glares aren't going to make a damn difference," he told her frankly.

Mikasa's heart sank, as understanding seemed to dawn upon Eren.

_Not now. Why is this happening now?_

Eren's eyes hardened.

"I see how it is, then."

His voice was cold, his words cutting through her like daggers.

"I'll leave you two then."

"Finally. Close the door, will you," Rivaille called after him.

Eren slammed the door shut and stormed off.

"Now then." Rivaille turned back to Mikasa, smirking as he pushed down towards the desk.

"No!" Mikasa jumped off his lap. "No - I - I have to find Eren!"

He watched her languidly, leaning back on his chair, as she hurriedly pulled her clothes on.

"This is over," Mikasa told him as she left the room.

"Fine," he answered her nonchalantly, crossing his legs as he picked up his cravat, which Mikasa had ripped off earlier. He careful smoothed out the wrinkles.

_You'll come back to me, Mikasa. You and Eren both. _

* * *

"E-Eren."

She found him at dinner that night, sitting with Armin. He ignored her.

"Eren," she said again, a little louder.

His gaze met hers, his eyes flashing dangerously.

"What do you want?"

"Can we talk, Eren? Please?"

"Can't you see I'm talking to Armin?"

"Just for a little while! It's important!"

The blonde boy seemed to notice there was something going on between the two. He stood up hastily, his blue eyes full of concern.

"Eren, it's okay. I think you should talk to Mikasa."

Eren stood up, his chair scraping against the ground. Without another word to either of them, he left the room.

* * *

"Eren!" Mikasa ran after him. "Eren, wait!"

She caught his arm, and he shoved her hand off, roughly.

"Don't _touch _me," Eren hissed, and Mikasa took a step back, stung.

"Eren, I'm sorry! Please let me explain."

"Explain what?!" he whirled around, his gaze boring into hers. "There's nothing to explain. I saw what I saw. I'm not a stupid kid, Mikasa. I understood what was happening."

"But I - Eren, it's not what you think."

Eren took a step towards her, gripping her shoulders tightly.

"Was that the first time?" he asked.

Mikasa wanted to lie to him, so badly. But when he looked at her with those brilliant green eyes, she found that there was no way that she would be able to bring herself to deceive him.

"N-no," she admitted.

Eren's grip tightened, his fingers digging into her shoulders.

"How long? How long was this happening?"

"About - about two months."

Eren exhaled loudly, releasing her and raking a hand through his hair in frustration.

Then -

"Was it - consensual?"

"H-huh?"

"Did you agree to it? Do it voluntarily? Or did he force you?"

"I - " Mikasa broke off, tears welling up in her eyes.

Eren's eyes softened for a moment, as he took in her anguished expression.

"Mikasa, if he did, please tell me. I know he's the Corporal, and maybe he's threatened your or something, and you couldn't say anything back then. But please, if there's anything like that going on, just tell me about it. We'll figure something out."

His voice was gentle this time, with a hint of pleading. Mikasa wanted to tell him that he was right. She wanted to break down there and then and run into his arms and let him comfort her. He would now, if she said that. She could tell. Eren was being protective right now, and he would do anything for her.

_Why now? Why now, why now, why now?_

The tears slid down her cheeks. Eren was shocked to see her openly crying.

"Hey, Mikasa... don't cry..."

He gathered her in his arms then, pulling her to him. It made Mikasa cry even more as she clenched his shirt between her fingers, feeling the deep, reassuring beat of his heart against her chest. He was warm, and she felt so safe, with Eren holding her.

It was different, the total antithesis to how she felt when she was with Rivaille - never safe, but always thrilled, challenged, pushed.

_I wish I could stay in Eren's arms forever._

But then she remembered how soft and demanding Rivaille's lips had been against hers, how she had willingly spread her legs for him as he pushed her down against his silken sheets.

And even though she loathed saying it, knew that Eren would hate her, Mikasa knew she couldn't lie to him. She reluctantly disentangled herself from him, knowing that he would probably never hold her again like that.

"He - didn't force me," Mikasa said, taking a deep breath. Eren's eyes never left hers. "It was - consensual."

"Then I have nothing to say to you anymore."

His gaze was like stone, and he sounded absolutely disgusted with her.

"Eren, I'm sorry!" Mikasa cried. "I won't do it again! You're more important to me! All I ever wanted was to be by your side-"

"And how the hell did you intend to stay by my side if you were busy fucking him?!"

He was shouting at her now, his expression furious.

"We were supposed to fight the Titans, Mikasa! That's what we came here for! And you and him were supposed to be humanity's two strongest soldiers! What the fuck were you two thinking, wasting time on that kind of crap?!"

"Eren, we only -"

"I used to idolize him, and you knew that! Rivaille-heichou, I always thought I wanted to be more like him! But you had to ruin that for me as well, didn't you? As if being the best at everything, all the time, wasn't enough?"

"The only reason I tried so hard was to protect you!" Mikasa cried. "That's all it's ever been about, Eren!"

"Well, I told you I never asked for that! I'm sick of you acting like my protector, Mikasa! It's suffocating. I don't want it!"

"You always - " Mikasa sniffed, her voice cracking. "You're always pushing me away, Eren. That's why it's so _hard. _I was lonely, and I messed up but I -"

"You were _lonely_?!" Eren scoffed. "Tch. Don't give me that bullshit, Mikasa. Don't push it on me and make it seem like its my fault."

"I'm not saying it's your fault, but I -"

"You always had Armin and the others. And I was there for you too. You just never looked at me as more than a little kid that needed protecting. That's what I always hated about you."

_-never looked at me as more than a little kid - _

Mikasa's heart swelled for a moment.

_Does that mean he wanted me to - _

"Wh-what's that supposed to mean?"

"What's _what _supposed to mean?!" he spat at her.

Mikasa steeled herself.

_I'll do it. I'll tell him now. There's nothing to lose. _

"Eren, I love you," she said breathlessly. "Or - I'm in love with you. I always have been, for a long time."

He stared at her, his brows furrowing. There was a long silence for a moment, and then -

"Is this supposed to be some kind of a sick joke?!"

Her stomach plummeted at his tone. He sounded frustrated, angry, more _annoyed _than anything.

"No, I mean it," she said. "I love you, Eren."

"I find that hard to believe, when you've been busy doing fuck knows what with the Corporal."

"It's because I was lonely! You were always pushing me away and -"

"Please, Mikasa. Both you and I know that's not it."

His voice was like steel, hard and unyielding.

"Even so," Mikasa persisted. "The way I feel about you - I'm not lying, Eren, I -"

"I don't want to hear it, Mikasa," Eren snapped at her. "What the fuck is wrong with you?! Do you really think I want to hear that kind of thing from you, especially now?!"

Mikasa felt her heart crack, feeling suddenly dizzy.

_No - he doesn't - Eren doesn't - _

"I always cared about you a lot, probably more than anyone. But this - you've lost it. I don't even want to _look _at you anymore. I don't care if you say you want to protect me, that you _love _me or whatever. Just stay the hell away from me, Mikasa."

And then he was gone, and Mikasa fell to the floor on her knees, tears streaming out of her eyes.

_Eren doesn't love me._

On that day, Mikasa Ackerman learned what heartbreak felt like.

* * *

_Author's Note: ...troll ending there trying to rip off the SnK tagline thing. Please review and let me know what you think of the chapter!_

_Special thank you to all those who reviewed the last chapter! :) _


	3. Corporal

_Disclaimer: I don't own Shingeki no Kyojin_

_Author's Notes: Okay, I did not expect so many reviews for this beyond depraved piece of smut. But you people are fantastic. I love you all so much, in an entirely non-creepy way. I'm sorry for all the angsty Eren and for torturing the poor boy, and Mikasa. It'll continue for 1-2 more chapters, all this, till they finally have their OT3 time. Yay. _

_It made me smile the way some of you were siding Eren and Mikasa last chapter. Frankly, I felt sorry for the both of them, it's all just a very messed up situation. Which will soon get resolved. And then everyone will be happy. _

_Warning: Rated M for sMut, as usual. This chapter contains LeviEren or Riren towards the end. You have been warned. I'm really sorry if that bothers anyone/makes me lose readership. But from the outset, this was an ot3 story (with a mix of all three of the in their respective couple ships or whatever you call them) so I'm trying to stick to that and make it work._

* * *

**Fraternization**

**Chapter 3: Corporal **

* * *

For the next few days, Eren pretty much ignored Mikasa completely. It wasn't hard given that they had entirely different training regimens.

Mikasa's consisted of her training privately with Rivaille. It boiled Eren's blood just thinking of it.

Her words from before echoed in his head.

_'I'm in love with you. I always have been, for a long time.'_

But then there was still that image of her, entwined around Rivaille, imprinted in his mind.

Eren clenched his fists, eyes stinging at the memory.

_Mikasa... how could you?!_

* * *

"Lighten up."

Mikasa glowered at the man.

"Fuck you, heichou."

"Not when you're so depressed. You wouldn't be much fun."

Mikasa wanted to pounce at him then, and pound him to the ground. He stood there, infuriatingly calm, his arms crossed as he watched her swing through the trees, cutting down wooden Titan after wooden Titan.

"This is all _your _damn fault!" she seethed.

"My fault?" he raised an elegant eyebrow at her. "I admit, locking the door would have been a good idea. But other than that, you were as much into it than I was, if not more."

Mikasa hated him at that moment, hated him more than she ever had. He hadn't made a move to touch her, ever since Eren had walked in on them. A part of her wanted him to, just so that he would get close enough for her to scratch his eyes out.

Her heart ached as she thought of Eren, and his betrayed, shocked expression.

"Eren... I'm so sorry..." she murmured aloud.

She flew through the air, whirling around as she sliced down more Titan cutouts, landing gracefully on the ground in front of him once she finished off the last.

Mikasa sheathed her blades. Levi looked unimpressed.

"Again."

"What?!"

"That was pathetic. Too slow. I got bored watching you. Do it again."

Mikasa's lips curled back in a snarl, and it took every ounce of her self control not to attack _him _instead. She turned around and shot back into the air, attempting the course for the fifth time that day.

* * *

"DIE! DIE YOU FUCKERS!" Eren raged as he sliced through the Titan's neck with two parallel cuts.

It had been a few months since the Castle Utgard incident, and Titans wandering around within Wall Rose was no longer unheard of. That day, a group of them had converged around the Scouting Legion's headquarters.

"Eren, you moron!" one of the scouts called. "Get back here! Heichou's orders were to keep you inside and safe! Let us deal with them!"

_Fuck Heichou and his orders. Both he and Mikasa treat me like I'm a kid. They think they're the only ones capable of killing all the Titans, and - _

"Tch," Eren spat, gritting his teeth as he swung over another Titan's shoulder, hacking viciously at it's neck.

Once that was one was down, he shot into the mass of Titans that was gathered near the stables, managing to bring down another three, despite the yells of his squad members.

It was too late when he noticed the large hand looming over him.

"Eren!" someone screamed.

"You bastard," Eren choked out, as the hand squeezed. He bought his thumb to his mouth.

He knew he wasn't in any danger. He'd transform and crush them, crush them all. Rushing headfirst into such a large crowd of Titans without enough trees or buildings around for leverage was suicide for anyone on 3DMG, no matter how skilled. But Eren knew he could do it, with his powers.

But before he could bite his thumb, there was a blur of color and a flash of blades. The hand around him dissipated away, and Eren immediately shot his 3DMG hooks out, propelling himself away from the mess momentarily.

He spun around midair to look for his savior, and saw Mikasa spinning around furiously, cutting down Titan after Titan.

A spasm of fear shot through him.

_That idiot! What does she think she's doing?! _

Eren jerked himself forwards, shooting towards Mikasa, but a hand tugged at his jacket, pulling him backwards.

"What the fuck-"

Eren turned around, his angry eyes meeting the narrowed ones of the Lance Corporal.

"Eren. You're supposed to be in the castle."

"Don't fucking tell me what to do! I'm killing the bloody Titans! And right now Mikasa is -"

"You trying to save her won't solve anything. She'll just try to save you all over again and you'll both be in deeper shit. Stupid brats."

And then without a backwards glance at Eren, Rivaille flew into the rabble of Titans at lightning speed. Eren could barely follow his movements, but somehow he managed to grab Mikasa and extract her from the mess, meanwhile cutting down at least five or six Titans himself.

Rivaille released her when they had reached a tree, the very same tree Eren was now standing on. He all but dumped her on the thick branch. Mikasa glared at him.

"Both of you little shits need to learn to follow orders," Rivaille snapped at them. "Mikasa, use your brains for once and stop running after Eren every time. He's an impulsive idiot who will get himself eaten, but unlike you, he can transform and regenerate. And Eren. Get back to the castle _now._"

Eren threw one last dirty look at Rivaille, ignoring Mikasa completely, but obeyed, and sped back to the castle.

"Eren - " Mikasa called after him, but stopped with Rivaille gripped her shoulder tightly.

"Now's not the time. Focus on the Titans."

"But - "

Rivaille sighed.

"He doesn't hate you. He was all ready to jump to your rescue right now, and would have if I hadn't stopped him. Now stop crying like a fucking baby and do your duty as a soldier."

* * *

_Fuck him. Fuck him! If I was a Titan I probably could tear him to pieces._

Eren paced through his little underground room, his hands fisted by his side.

Sometimes, he really wanted to punch Lance Corporal Rivaille _hard _across the face. Off late, ever since the incident with Mikasa, those feelings were intensifying.

_Who do they think they are?!_

The image flashed through his mind - of Mikasa, straddling Rivaille's lap, her legs wrapped around him as she moved against him. She had been topless, just pale smooth skin under the straps of her 3DMG.

Eren had caught a glimpse of her bare chest, the way Rivaille's tongue had flicked against her skin, the way those fingers had trailed teasingly across Mikasa's bare back, taunting Eren.

Rivaille had been shirtless as well, all lean muscle like Mikasa, but buffer, with broader shoulders. His arms must have been unimaginably strong from all that Titan slaying, from the look of his biceps and the way they had flexed when he held Mikasa.

Eren hadn't paid it much thought then, he had been too furious. But now, as he sat in his room, not doing much of anything, he couldn't forget the way Mikasa's fingers had fisted Rivaille's hair, or the way Rivaille's hands had held her waist possessively.

It bought up a flare of anger within him, and he wished that he could forget it entirely.

But there was another part of him that couldn't forget, that didn't _want _to forget.

_What the hell is wrong with me?!_

Eren shook his head, clearing his thoughts. But a moment later, his door swung open.

"What do you want?!" Eren growled, as Rivaille sauntered in.

"Your room is filthy. Do you ever wash it?" was the man's response.

"Why are you even down here. Shouldn't you be _training _with Mikasa?"

"Jealousy doesn't suit you, Eren," Rivaille remarked lightly.

"What the hell do you mean?!"

"Use your stupid little head. You'll figure it out."

"I'm not interested in your fucked up games!"

"Maybe you're not," Rivaille sat down on Eren's bed, reclining against the wall as he crossed his legs.

He was sitting there, so casually - as if Eren wasn't aware of what he had been doing with Mikasa for the past two months - it infuriated Eren.

"If you have no reason to be down here, could you please get the fuck out?"

"Careful, Eren," Rivaille warned. "Unless you want me to clean that shitty little mouth for you."

"Huh-"

Rivaille smirked. "Oh, I have my ways."

"I don't even know what you're saying. Get out."

"You know," Rivaille said after a moment. "If you wanted it that much, you could have just asked Mikasa. I wouldn't have given two shits."

"What are you even talking about?"

"It may have been a little awkward at first, since you're nowhere near as experienced as I am... but I'm sure even you'd figure it out soon enough."

Eren's mouth went dry as the meaning of Rivaille's words dawned upon him, and he was unable to believe his ears.

"What - I don't - want - that - " he sputtered, his cheeks reddening.

"Give it up, Eren." Rivaille rolled his eyes. "Mikasa may fall for your tantrums, but I can see right through them. You're jealous."

"I'm not jealous of you!" Eren spat, his eyes blazing. "That's the most retarded thing I've heard!"

And then suddenly, Rivaille had grabbed him by the shirt and yanked him down, till their faces were inches apart.

"Is that so? Then maybe you're jealous of Mikasa? Hm?"

His voice was low, velvety smooth - and Eren felt a shiver go down his spine. He could feel the Corporal's warm breath ghosting against his skin.

"Hei - chou -" Eren bit out, unable to say anything else.

Rivaille smirked then, a single finger trailing across Eren's collarbone.

"That's what it is, isn't it? You want some too, don't you, Eren? Dirty, horny little shit."

His words were biting, condescending - but Eren's skin felt like fire under his touch - and he could smell the Corporal's scent, feel Rivaille's bangs brushing his forehead.

Eren couldn't help but lean forwards, just a tiny bit. He would never admit it, but he found himself craving more of the man's touch. Rivaille's smugness and self-assurance was aggravating, but at that moment -

_Is this how Mikasa felt, when - _

The Corporal's knee brushed against Eren's leg, and he felt himself harden involuntarily.

_Shit! This can't be happening!_

But Rivaille only shoved Eren away, before standing up suddenly, in one fluid moment. His cold gaze swept over Eren's form.

Eren gulped, as Rivaille narrowed his eyes.

"You sick fuck. I barely touched you and you're already getting off on it? What would Mikasa say?"

And then he left the room without another word, leaving Eren with a bright red face and a throbbing erection.

* * *

That night, Eren dreamed of Rivaille and Mikasa. He didn't know if it was a dream as much as it was a nightmare.

He dreamed of Rivaille shoving her back onto his desk, working his lips over her body. He dreamed of Mikasa arching her back under Rivaille's touch, her normally calm and controlled countenance flushed.

_"Heichou," Mikasa gasped, her voice trembling. "Rivaille-heichou!"_

_Rivaille thrust against her, pressing her to him. Mikasa's dark eyes were filled with lust, her lips glistening, her black hair fanned out below her. _

_"Please," she begged. "Please - "_

_He thrust into her again, but this time when she cried out, it was a different name on her lips._

_"Eren! Oh - Eren - "_

_And then it was him on top of her, holding her, thrusting into her. Mikasa's nails scraped against his bare back. _

_"Eren, please - "_

_Eren leaned down to kiss her, but then__ suddenly, Mikasa was gone, her wide eyes replaced by smoldering icy blue ones._

_"You!" Eren jerked his head back, horrified. _

_Rivaille smirked, flipping him over. _

_"You little shit. Stop denying it. You want me to fuck you, don't you? Just like I fucked Mikasa."_

"What the - " Eren groaned, sitting up in his bed. He stared down at his hand in horror, and his now sticky sheets.

_What did I just - _

And then the Titan shifter bought his knees to his chest, banging his head against them.

"Fuck my life."

* * *

_Author's Notes: Yup. Okay. I have no words for myself. There will be MikaEren in the next chapter. Since that's the only pairing here that has gotten no 'action' as such, just a lot of fighting/angst/verbal development. Along with RivaErenMika (finally!) if all goes as planned. _

_Please review!_

___PS - **I finally got a tumblr! **No idea how to use it, but follow/friend/whatever me! The link is on my profile page. _


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